Performers who wear costumes of characters like Elmo and Spider-Man have become common sights in the busy tourist spot. They ham it up with children and post for photos — then ask the parents for tips, sometimes aggressively.

This copy is for your personal, non-commercial use only. Distribution and use of this material are governed by our Subscriber Agreement and by copyright law. For non-personal use or to order multiple copies, please contact Dow Jones Reprints at 1-800-843-0008 or visit www.djreprints.com.